Extreme Weather Frequency

Extreme Weather Frequency. Impacts due to altered frequencies and intensities of extreme weather, climate, and sea level events are very likely to change.

Since the IPCC Third Assessment (TAR), confidence has increased that some weather events and extremes will become more frequent, more widespread and/or more intense during the 21st century. Since the TAR, more is also known about the potential effects of such extreme events. A selection of these is presented in the IPCC Extreme Weather Frequency Table below.

Phenomena
and direction
of trend

Likelihood of future
trend based on
projections for 21st
century using SRES
scenarios

Costs of coastal protection
versus costs of land-use
relocation; potential for
movement of populations
and infrastructure; also
see tropical cyclones
above

Explanation for the IPCC Table above. Examples of possible impacts of climate change due to changes in extreme weather frequency and climate events, based on projections to the mid to late 21st century. These do not take into account any changes or developments in adaptive capacity. The likelihood estimates in Column 2 relate to the phenomena listed in Column 1. The direction of trend and likelihood of phenomena are for IPCC SRES projections of climate change.

Current observations appear to show an increase in ‘extreme weather frequency’. Visit our extreme weather page to see events over the past month.